<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <div id="app">
    <a href="/home">home</a>
    <a href="/about">about</a>
    <div class="content">Default</div>
  </div>

  <script>
    const contentEl = document.querySelector('.content');

    const aEls = document.getElementsByTagName("a");
    for (let aEl of aEls) {
      aEl.addEventListener("click", e => {
        e.preventDefault();
        const href = aEl.getAttribute("href");
        // history.pushState({}, "", href);
        history.replaceState({}, "", href);
        // console.log(111111)
        // changeContent()
      })
    }

    const changeContent = () => {
      console.log('1111')
      switch (location.pathname) {
        case "/home":
          contentEl.innerHTML = "Home";
          break;
        case "/about":
          contentEl.innerHTML = "About";
          break;
        default:
          contentEl.innerHTML = "Default"
      }
    }

    window.addEventListener("popstate", changeContent)
  </script>

</body>

</html>